Expression of inducible nitric oxide synthase in rat junctional epithelial cells

结膜上皮（JE）比口腔黏膜上皮（OSE）和口腔上皮（OE）更早受到引起牙周炎症的刺激的影响。一氧化氮（NO）具有多种生物活性，被认为可以调节炎症。NO是由l-精氨酸合成的NO合成酶（NOS），分为神经型NOS （nNOS）、内皮型NOS （eNOS）和诱导型NOS （iNOS）。转录因子NF-kappa B在iNOS基因的转录调控中起关键作用。本研究研究了大鼠牙龈组织中iNOS、eNOS和nf - κ B的免疫组化表达。研究了神经肽P物质（SP）对脑炎细胞iNOS表达的影响。iNOS、eNOS和NF-kappa B的免疫反应产物遍布龈内各种细胞（JE细胞、OSE细胞、OE细胞、成纤维细胞和内皮细胞）。在牙龈中，以10-4 M的浓度施用SP 30 min后，未检测SP对乙脑细胞iNOS表达的影响。有人认为，乙脑细胞可能产生一氧化氮，并形成一道防线，以抵御有害的刺激，如细菌。需要进一步的研究来确定NO在乙脑细胞中的作用。

The junctional epithelium (JE) is affected earlier than oral sulcular epithelium (OSE) and oral epithelium (OE) by stimuli that evoke periodontal inflammation. Nitric oxide (NO) has a variety of biological activities and is thought to modulate inflammation. NO is generated from L-arginine by NO synthases (NOS), classified into neural-type NOS (nNOS), endothelial-type (eNOS) and inducible-type (iNOS). The transcription factor NF-kappa B plays a critical role in the transcriptional regulation of iNOS gene. In this study we investigated the immunohistochemical expression of iNOS and eNOS and NF-kappa B in rat gingiva. And we also investigated the effect of neuropeptide substance P (SP) on expression of iNOS in JE cells.The immunoreactive products of iNOS, eNOS and NF-kappa B were found throughout various cells (JE cells, OSE cells, OE cells, fibroblasts and endothelial cells) in the gingiva. In the gingiva, 30 min after SP application at concentrations of 10-4 M, the effect of SP on expression of iNOS in JE cells was not detected immunohistochemically. It was suggested that JE cells might produce NO and form a line of defense against harmful stimuli such as bacteria. Further studies are needed to determine the role of NO in JE cells.